Package: mktemp
Version: 1.5-2
Severity: normal

mktemp can be given templates which expand to the same name at every
use. It seems that it will only enter random characters into the "X"
letters from the template if they are at the end, so this can easily
happen by mistake. This leads to an unexpected denial of service
vulnerability, triggered if a file with that name already exists.

Such a mistake in a script can (and did until recently) go unnoticed if,
e.g., an erroneously appended ".tmp" suffix leads to a valid, although
not randomly named temporary file. This was only noticed when such a
file was lingering around from a failed run and the new instance's error
message suspiciously still contained all the "X" letters from the
template.

Consider this example:

  $ mktemp foo.XXXXXX
  foo.S26762
  $ mktemp foo.XXXXXX
  foo.i28529

  $ mktemp foo.XXXXXX.tmp
  foo.XXXXXX.tmp
  $ mktemp foo.XXXXXX.tmp
  mktemp: cannot create temp file foo.XXXXXX.tmp: File exists

The first two mktemp invocation result in two randomly and differently
named temporary files, as expected. The third invocation creates a file
with a predictable name, and the fourth fails as this file already
exists.

-- System Information:
Debian Release: 4.0
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.18-6-686
Locale: LANG=de_DE, LC_CTYPE=de_DE (charmap=ISO-8859-1)

Versions of packages mktemp depends on:
ii  libc6                  2.3.6.ds1-13etch5 GNU C Library: Shared libraries

mktemp recommends no packages.

-- no debconf information



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